Another heat problem
Thread Starter
AudiWorld Newcomer
Joined: Jan 2024
Posts: 2
Likes: 0
Another heat problem
I have a 2006 Audi A4 2.0. I have not had heat for three years in the car but it never bothered me being I live in Florida. My gauge for the heat is reading normal. No overheating issues. I changed out the heater core, which had a bunch of sediment in it. After changing it and flushing, bleeding out the air the only time I had heat was if I had the engine rev. When the car sits at idle, the air gets cold. The hoses going into the firewall The lower or input side is hot. The output side is kind of cooler to touch. So my question is after changing out the heater core and still not having heat and I’m not having any overheat problems, What should I be looking at.? No leaks in the system as far as I can tell. No loss of coolant. Should the two lines be different temps or close to the same?
AudiWorld Senior Member
Joined: Oct 2009
Posts: 1,118
Likes: 127
From: Victoria, B.C., Canada
Sounds like you have air in the core. The in and out should be the same temp or close to it. Try pulling the upper hose and burping the system. Usually I go for a run after doing a core flush and that seems to get all the bubbles out.
AudiWorld Member
Joined: Oct 2001
Posts: 99
Likes: 6
From: Nor Cal
+1 to Cybersombosis - I had issues getting air out of the heater core in my A4 for years. Both heater core hoses should be equally hot with steady circulation once the thermostat is open. The factory way to bleed the whole system is to use the bleeder holes on the heater core hoses. When hot, carefully pull back one hose only until air bubbles start coming out (be careful it's hot). Keep running until a solid stream comes out of the bleed hole. I found you need to do it at 1500-2500 RPM. But before doing this, the method I just used was to undo the heater hoses there at the firewall and fill the heater core manually with coolant - pour water in one hose until it flows through, then re-attach both hoses and take it for a drive, top up coolant in the reservoir and then bleed the system to see if there is any air. It took me more than a few tries, but my heater now blows hot again.
Thread
Thread Starter
Forum
Replies
Last Post
